Locking mechanism for jewelry

ABSTRACT

An openable jewellery item arranged to be worn about a portion of a body of a person comprises two arcuate sections pivotally interconnected at one end for permitting pivotal movement of the sections between opened and closed positions, a locking surface disposed on each arcuate section at a second end, each locking surface cooperating with the facing locking surface of the other arcuate section for releasably retaining the arcuate sections in a closed position; the two locking surfaces each having oppositely facing hook contours; one locking surface has a weakened length to provide springiness. A pivotal section connects between the two arcuate sections to tension the sections towards the opened position, and in variations to tension the hooks to engage. A release is pressed to disengage the hooks. A variation has catches at both sides to allow complete separation of the sections.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to a locking mechanism for jewelry and, more particularly, but not exclusively, to a locking mechanism for a bangle, bracelet or ring.

There are numerous types of locking mechanisms for jewelry. Bangles with hinges at one end and a latch at the opposite end have been popular since the Victorian age. One form of latch is the box and tongue closure, in which a tongue element engages with teeth within a box. The elements of the system lose their alignment or springiness easily, requiring frequent adjustment and overall they wear out easily, limiting the lifetime of the jewelry item. Variations are the tongue and groove box clasp, and a two-pronged tongue and groove catch. A variation uses a pin to engage a hole in the teeth within the box. Here the pin tends to lose alignment over time.

In variations used for example in the more valuable watches, the tongue and box mechanism is augmented by a safety clasp. The safety clasp ensures that the watch will not be lost on wearing away of the main catch mechanism but does not alter the fact that the main catch mechanism does wear away or need adjustment. In addition the safety clasp represents in itself a considerable increase in complexity of the product and may harm the aesthetics of the design.

Many prior art locks require at least some stainless steel for strength, and gold may be difficult to plate onto stainless steel. Such locks may also be intricate and may thus be labor-intensive to produce.

In more recent art, U.S. Pat. No. 7,107,789 to Bruner, describes an openable ring that is arranged to be worn about a portion of a finger etc. The ring includes first and second arcuate sections that are pivotally interconnected at one end of the ring for permitting pivotal movement of the arcuate sections between opened and closed positions. At the end opposite the pivotal interconnections, each arcuate section includes a pair of locking extensions which are traversely aligned with one another. Each locking extension has a locking surface which comprises a sum of more than one hill and valley portion. These portions cooperate with one another to releasably retain the arcuate sections in a closed position to define a closed ring having an inner surface and an outer surface, the inner surface fitting around the finger.

Again, the alignment is easily lost, requiring frequent adjustment.

In all of the above, the locking mechanism requires alignment and soldering, requiring experienced jewelers to carry out the manufacturing process.

SUMMARY OF THE INVENTION

The present embodiments provide an item of jewellery or the like which does not require frequent adjustments and in which the lock and safety are all in one part.

The present embodiments can be manufactured without requiring soldering, hence reducing the need for expensive manufacturing skill, and more generally lead to ease of manufacture and assembly. By contrast, the locks of the existing art require skilled jewelers to carry out soldering and alignment.

Furthermore, the present embodiments are amenable to plating with any required metal.

According to an aspect of some embodiments of the present invention there is provided an openable jewellery item arranged to be worn about a portion of a body of a person, said item comprising:

first and second arcuate sections interconnected at first ends of said sections for permitting movement of said arcuate sections between opened and closed positions, said arcuate sections also having a second end opposite the pivotal interconnection;

a locking surface disposed on each arcuate section at said second end, each said locking surface provided for cooperating with a locking surface of the other arcuate section for releasably retaining the arcuate sections in a closed position;

said locking surface on said first arcuate section comprising an internally facing radially externally located hook contour;

said locking surface on said second arcuate section comprising a weakened length to provide springiness and an externally facing internally located hook contour;

said item in its closed position comprising a locking engagement of said hook contours of said locking surfaces;

a pivotal section connected between said first and second arcuate sections to tension said arcuate sections towards said open position; and

a release disposed on said locking surface on said second arcuate section, said release being pressable from said closed position to a disengaging position wherein said externally facing internally located hook contour is disengaged from said internal facing externally located hook contour.

In an embodiment, said pivotal section is connected via two hinges to said second arcuate section and by one hinge to said first arcuate section.

In an embodiment, said second arcuate section has a thickness, said weakened length being about 40% of said thickness.

In an embodiment, said release comprises a button mounted on said weakened length.

In an embodiment, said pivotal section is movable between a first stable position in which said arcuate sections are held open and a second stable position in which said arcuate sections are held closed.

In an embodiment, wherein said interconnection comprises a hinge.

In an embodiment, said interconnection comprises oppositely facing hooked contours.

In an embodiment, said pivotal section is pivotally connected at either side thereof to respective locking surfaces at either end of said second arcuate section to tension respective hooked contours radially outwardly against corresponding hooked contours of said first arcuate section.

The item may be a bracelet, a bangle, a ring, an earring, a finger ring, a watch or any item based on a toroidal shape which requires latching.

According to a second aspect of the present invention there is provided a method of manufacture of an openable jewelry item for wearing about a portion of a body of a person, the method comprising:

providing first and second arcuate sections;

interconnecting said first and second arcuate sections at first ends respectively of said sections for permitting movement of said arcuate sections between opened and closed positions, said arcuate sections also having a second end opposite the pivotal interconnection;

disposing a locking surface on each arcuate section at said second end, each said locking surface being arranged to cooperate with a locking surface of the other arcuate section for releasably retaining the arcuate sections in a closed position;

providing said locking surface on said first arcuate section with an internally facing radially externally located hook contour;

providing said locking surface on said second arcuate section with a weakened length to provide springiness and an externally facing internally located hook contour; arranging said item with a closed position in which said hook contours of said locking surfaces are in locking engagement;

providing a pivotal section connected between said first and second arcuate sections to tension said arcuate sections towards said open position;

disposing a release on said locking surface on said second arcuate section, said release being pressable from said closed position to a disengaging position wherein said externally facing internally located hook contour is disengaged from said internal facing externally located hook contour.

Unless otherwise defined, all technical and/or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the invention, exemplary methods and/or materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and are not intended to be necessarily limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the invention are herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the invention. In this regard, the description taken with the drawings makes apparent to those skilled in the art how embodiments of the invention may be practiced.

In the drawings:

FIG. 1 illustrates a bangle according to a first embodiment of the present invention;

FIG. 2 is a simplified schematic diagram which shows the bangle of FIG. 1 in a closed position after depression of release;

FIG. 3 is a simplified schematic diagram which illustrates two arcuate sections after a hook has disengaged and been pushed down and the bangle begins to open;

FIG. 4 is a simplified schematic diagram which illustrates the bangle in the open position;

FIG. 5 is a simplified schematic diagram showing a perspective view of the bangle in the open position of FIG. 4;

FIGS. 6, 7 and 8 are simplified schematic diagrams showing a variation of the bangle of FIG. 1 in the closed, released and partly open positions of FIGS. 1, 2 and 3;

FIGS. 9-11 are simplified schematic diagrams showing cross sections of the catch mechanism in closed, partly released and released positions respectively;

FIG. 12 is a simplified schematic diagram illustrating a bangle according to a second embodiment of the present invention wherein there is no extension of the pivoting section or the lower arcuate portion beyond the hinge;

FIG. 13 is a simplified view of the bangle in the closed position from a varied perspective, of the bangle of FIG. 12;

FIG. 14 is a detail in perspective of the lower arcuate section and locking element of the bangle of FIG. 12;

FIG. 15 is a simplified diagram illustrating an alternative arrangement of the release mechanism and button of FIG. 12;

FIG. 16 is a simplified diagram showing the bangle release mechanism of FIG. 15 during disengagement of the hooks;

FIG. 17 is a simplified diagram showing the release mechanism of FIG. 15 at a further stage of the hook disengagement;

FIG. 18 is a simplified diagram showing the bangle of FIG. 15 after release;

FIG. 19 is a simplified diagram illustrating the alternative arrangement of the release mechanism and button of FIG. 15, in cross section;

FIG. 20 is a simplified cross-sectional diagram showing the bangle release mechanism of FIG. 15 during disengagement of the hooks;

FIG. 21 is a simplified cross-sectional diagram showing the release mechanism of FIG. 15 at a further stage of the hook disengagement;

FIG. 22 is a simplified cross-sectional diagram showing the bangle of FIG. 15 after release;

FIG. 23 is a simplified diagram showing a bangle according to a third embodiment of the present invention, in which the first and second arcuate sections are not hinged;

FIG. 24 is a simplified diagram showing the bangle of FIG. 23 wherein the catch begins to be released;

FIG. 25 is a simplified diagram showing the bangle of FIG. 23 with the catch further released;

FIG. 26 is a simplified diagram showing the bangle of FIG. 23 during a yet further stage of the release; and

FIG. 27 is a simplified diagram showing the bangle of FIG. 23 after both catches have been released.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to a lock or a clasp and, more particularly, but not exclusively, to a lock or a clasp for an item of jewelry.

The present embodiments may provide a lock or clasp for jewelry that aims for ease of production and provides jewelry that is easy to plate. The lock can be made out of brass, which can be plated with copper, silver or gold. As mentioned, many prior art locks require at least some stainless steel for strength, and gold may be difficult to plate onto stainless steel.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or the Examples. The invention is capable of other embodiments or of being practiced or carried out in various ways.

Referring now to the drawings, FIG. 1 illustrates a jewelry item according to the present embodiments. Specifically a bangle 10 is shown. The bangle is openable so as to slide onto the arm of the wearer and then can be closed. The bangle includes first 12 and second 14 arcuate sections pivotally interconnected at one end of the bangle by hinge 16. The arcuate portions are shown in their closed position in FIG. 1 but are in their open position in FIG. 4, and hinge 16 permits pivotal movement of the arcuate sections between the opened position of FIG. 4 and the closed position of FIG. 1.

The arcuate sections also share a second end 18 opposite the pivotal interconnection 16.

At the second end each arcuate section has a locking surface 20, 22. The locking surfaces, 20, 22, cooperate with a locking surface 22, 20 of the other arcuate section for releasably retaining the arcuate sections 12 and 14 in a closed position.

The locking surface 22 of the first arcuate section 12 comprises an internally facing externally located hook contour 24.

The locking surface 20 on the second arcuate section 14 comprises a weakened length 26 to provide springiness and an externally facing internally located hook contour 28. The weakened section may be formed by making the section of thinner material than the rest of the arcuate section, and it is noted that the aim of the weakened section is to provide springiness as opposed to brittleness.

The bangle when locked involves locking engagement between the hook contours 24 and 28 of locking surfaces 20 and 22.

A pivotal section 30, shown in hashed lines, is connected between the first 12 and second 14 arcuate sections and is hinged to the upper arcuate section 12 at hinge 32, and to the lower arcuate section 14 at hinge 34. Pivotal section 30 provides a radially outwardly pressing tension against the second arcuate section, tending to press the locking surface 20 and hook 28 radially outwardly into the open position. The springiness of the weakened section 26 allows hook contour 24 to slide under hook 28 and effectively engage hook 28 to snap the bangle in the closed position.

Pivotal section 30 extends beyond hinge 34 towards second end 18. In the closed position, the extended part of the pivotal section 30 clips onto the locking section 20. In the open position, as shown in FIG. 4 the extended part extends outwardly of the lower arcuate section 14. The extended part may be pressed to clip the bangle closed.

A release 36 is disposed on the locking surface 20 on the second arcuate section 14. The release can be pressed when the bangle is in the closed position and has the effect of disengaging hook 28 from hook 24, thus allowing the bangle to be opened.

FIG. 2 is a simplified schematic diagram which shows the bangle of FIG. 1 in the closed position after depression of release 36. The hook 28 disengages with hook 24 so that the two arcuate sections can be separated.

FIG. 3 is a simplified schematic diagram which illustrates the two arcuate sections after hook 28 has disengaged and been pushed down and the bangle begins to open.

FIG. 4 is a simplified schematic diagram which illustrates the bangle in the open position. Pivotal section 30 holds the two arcuate sections apart as it loses its tension.

FIG. 5 is a simplified schematic diagram showing a perspective view of the bangle in the open position of FIG. 4.

FIGS. 6, 7 and 8 are simplified schematic diagrams showing a variation of the bangle of FIG. 1 in the closed, released and partly open positions of FIGS. 1, 2 and 3. Parts that are the same as in the earlier figures are given the same reference numerals and are not described again.

In the embodiment of FIGS. 6-8 button 36 is replaced with a latch that comprises a springy extension 40 extending from the lower arcuate portion 14, and button 38. Depressing the button 38 causes the springy extension 40 to bend and force down protrusion 42, which in turn presses on weakened section 26 and pushes hook 28 radially inwardly to disengage it from hook 24.

FIGS. 9-11 show cross sections of the catch mechanism in closed, partly released and released positions respectively.

Operation of the catch mechanism is now described. In the two variations of the embodiment of FIGS. 1-11, the bangle construction consists, as stated, of three parts, an upper arcuate portion 12, and a lower arcuate portion 14 which are hinged to each other at a first hinge 16. The pivoting section 30 is connected to the upper arcuate portion 12 at a second hinge 32 and to the lower arcuate portion 14 at a third hinge 34. The pivoting section 30 may be tensioned to try and separate the two arcuate portions into an open position, and has an extension which extends outwardly of the lower arcuate portion 14 in the open position and which can be pressed to close the bangle. The upper and lower bodies snap together via a catch. The catch is made of a hook 28 on the lower body that catches a second hook 24 on the upper body. The lower tooth is on the end of a section of thinned metal 26 on the lower body 14 so as to provide springiness. As the user presses the extension of the pivotal section, the arcuate portions come together and the pivoting section snaps into position flush with the lower arcuate portion. The upper and lower arcuate sections slide together and hook 28 slides under hook 24 and then is pushed outwards by the springiness of the weakened length 26 to snap the catch closed thereby locking the upper and lower bodies together.

The button 36, 38 can be depressed to disengage the lower tooth and release the upper tooth to separate the upper body from the lower body to open the bangle.

FIGS. 12-22 are simplified schematic diagrams which illustrate a variation of the embodiment of the bangle of FIG. 1 in which there is no extension of the pivoting section 30 or the lower arcuate portion 14 beyond hinge 34. Parts that are the same as in the previous figures are given the same reference numerals and are not described again except as needed for an understanding of the present embodiment. FIG. 12 is a perspective view of the bangle in the closed position. Locking element 50 is attached to both lower arcuate section 14 and pivotal section 30 at hinge 34 and includes inter alia the lower locking surface 20, the weakened length 26, the hook 28 and button release 36. Function is as for the embodiments of FIGS. 1-11.

FIG. 13 is a view of the bangle in the closed position from a slightly varied perspective.

FIG. 14 is a detail in perspective of the lower arcuate section 14 and locking element 50.

FIG. 15 illustrates a variation of the embodiment of FIG. 12 in which the release mechanism and button 36 are arranged differently. Button 36 presses on bulge 52 to release hook 28, as follows. Pivotal section 30 is connected between hinges 16 and 30. When button 36 is pressed, locking element 50 is flexed outwards due to its springiness, and at the same time held in position due to hinge 34, which in turn limits the movement of hinge 53, so that the end part 55 of the single lock slides back, meaning towards hinge 34.

The locking surface 20 on the second arcuate section 14 is pivoted at hinge 53 against which the locking surface pivots due to the springiness and allows release of hook 24 from inside hook 28.

FIG. 16 shows the bangle when the hook 28 just disengages from the hook 24.

FIG. 17 shows the bangle with hook 28 a little further disengaged.

FIG. 18 shows the bangle with hook 28 released from hook 24.

FIGS. 19-22 show the bangle of FIG. 15 in the same three positions but this time the locking mechanism is shown in cross section. More particularly, FIG. 19 is a simplified diagram illustrating the alternative arrangement of the release mechanism and button of FIG. 15, in cross section;

FIG. 20 is a simplified cross-sectional diagram showing the bangle release mechanism of FIG. 15 and shows the bangle when the hook 28 just disengages from the hook 24. FIG. 21 is a simplified cross-sectional diagram showing the release mechanism of FIG. 15 at a further stage of the hook disengagement, hook 28 being further disengaged from hook 24 than shown in FIG. 20.

FIG. 22 is a simplified cross-sectional diagram showing the bangle of FIG. 15 after release of hook 28 from hook 24.

FIGS. 23-27 illustrate a fully detachable embodiment in which the first and second arcuate sections are not hinged to each other but instead the same hook catch mechanism is used for both sides, so that the connection is still pivotable, but not hinged.

In FIG. 23 bangle 70 is openable so as to slide onto the arm of the wearer and then can be closed. The bangle includes first 72 and second 74 arcuate sections which this time are not hinged, but as stated are still at least to some extent effectively pivotally interconnected. The arcuate portions are shown in their closed position in FIG. 23 but are in their open position in FIGS. 26 and 27. Catch mechanism 76 on a first side alternately allows pivotal movement of the arcuate sections between the opened position of FIG. 26 and the closed position of FIG. 23, and allows full detachment of the two sections as shown in FIG. 27.

At the second end there is catch mechanism 78 which is intended for regular locking and unlocking of the bangle. At both ends, each arcuate section has a locking surface 80, 82. The locking surfaces, 80, 82, cooperate with a locking surface 82, 80 of the other arcuate section for releasably retaining the arcuate sections 72 and 74 in a closed position.

The locking surface 82 of the first arcuate section 72 comprises an internally facing externally located hook contour 84.

The locking surface 80 on the second arcuate section 74 comprises a pivot 86 against which the locking surface pivots to provide springiness and allow release, as will be explained below. An externally facing internally located hook contour 88 extends from locking surface 82.

The bangle when locked involves locking engagement between the hook contours 84 and 88 of locking surfaces 80 and 82.

A pivotal section 100, shown in hashed lines, is connected between the pivots 86. Pivotal section 100 provides a radially outwardly pressing tension against the second arcuate section 74, tending to press the locking surface 80 and hook 88 radially outwardly so that hook contour 84 is effectively engaged in the closed position.

A release 92, shown in FIG. 26, is disposed on the locking surface 80 on the second arcuate section 74. The release can be pressed when the bangle is in the closed position and has the effect of disengaging hook 88 from hook 84, thus allowing the bangle to be opened. In order to disengage it may be necessary to press both buttons 92 in order to cause disengagement.

FIG. 23 shows the bangle in the closed position.

FIG. 24 shows catch 78 beginning to be released.

FIG. 25 shows catch 78 further released as hook 88 clears the end of hook 84 radially inwardly.

FIG. 26 shows a further stage of the release as hook 84 clears hook 88 downwardly but at the same time returns to its initial radial position.

FIG. 27 illustrates a stage in which both catches 76 and 78 have been released.

In the above it is noted that the catch mechanism is constructed of shaped parts that are connected together by hinges, thus obviating any need for soldering. The parts are easy to plate, and the latching is achieved with a single movement. Critical alignments are not needed and thus the construction does not need regular realignment as with the prior art.

The terms “comprises”, “comprising”, “includes”, “including”, “having” and their conjugates mean “including but not limited to”.

The term “consisting of” means “including and limited to”.

As used herein, the singular form “a”, “an” and “the” include plural references unless the context clearly dictates otherwise.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment, and the above description is to be construed as if this combination were explicitly written. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination or as suitable in any other described embodiment of the invention, and the above description is to be construed as if these separate embodiments were explicitly written. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting. 

What is claimed is:
 1. An openable jewellery item arranged to be worn about a portion of a body of a person, said item comprising: first and second arcuate sections interconnected at first ends of said sections for permitting movement of said arcuate sections between opened and closed positions, said arcuate sections also having a second end opposite the pivotal interconnection; a locking surface disposed on each arcuate section at said second end, each said locking surface provided for cooperating with a locking surface of the other arcuate section for releasably retaining the arcuate sections in a closed position; said locking surface on said first arcuate section comprising an internally facing radially externally located hook contour; said locking surface on said second arcuate section comprising a weakened length to provide springiness and an externally facing internally located hook contour; said item in its closed position comprising a locking engagement of said hook contours of said locking surfaces; a pivotal section connected between said first and second arcuate sections to tension said arcuate sections towards said open position; a release disposed on said locking surface on said second arcuate section, said release being pressable from said closed position to a disengaging position wherein said externally facing internally located hook contour is disengaged from said internal facing externally located hook contour.
 2. The item of claim 1, wherein said pivotal section is connected via two hinges to said second arcuate section and by one hinge to said first arcuate section.
 3. The item of claim 1, wherein said second arcuate section has a thickness, said weakened length being about 40% of said thickness.
 4. The item of claim 1, wherein said release comprises a button mounted on said weakened length.
 5. The item of claim 1, wherein said pivotal section is movable between a first stable position in which said arcuate sections are held open and a second stable position in which said arcuate sections are held closed.
 6. The item of claim 1, wherein said interconnection comprises a hinge.
 7. The item of claim 1, wherein said interconnection comprises oppositely facing hooked contours.
 8. The item of claim 7, wherein said pivotal section is pivotally connected at either side thereof to respective locking surfaces at either end of said second arcuate section to tension respective hooked contours radially outwardly against corresponding hooked contours of said first arcuate section.
 9. The item of claim 1, comprising one member of the group consisting of a bracelet, a bangle, a ring, an earring, a finger ring, and a watch.
 10. A method of manufacture of an openable jewelry item for wearing about a portion of a body of a person, the method comprising: providing first and second arcuate sections; interconnecting said first and second arcuate sections at first ends respectively of said sections for permitting movement of said arcuate sections between opened and closed positions, said arcuate sections also having a second end opposite the pivotal interconnection; disposing a locking surface on each arcuate section at said second end, each said locking surface being arranged to cooperate with a locking surface of the other arcuate section for releasably retaining the arcuate sections in a closed position; providing said locking surface on said first arcuate section with an internally facing radially externally located hook contour; providing said locking surface on said second arcuate section with a weakened length to provide springiness and an externally facing internally located hook contour; arranging said item with a closed position in which said hook contours of said locking surfaces are in locking engagement; providing a pivotal section connected between said first and second arcuate sections to tension said arcuate sections towards said open position; disposing a release on said locking surface on said second arcuate section, said release being pressable from said closed position to a disengaging position wherein said externally facing internally located hook contour is disengaged from said internal facing externally located hook contour.
 11. The method of manufacture of claim 10, comprising providing said pivotal section to be connected via two hinges to said second arcuate section and by one hinge to said first arcuate section.
 12. The method of manufacture of claim 10, comprising providing said second arcuate section with a thickness, said weakened length being about 40% of said thickness.
 13. The method of manufacture of claim 10, comprising providing said release with a button mounted on said weakened length.
 14. The method of manufacture of claim 10, comprising making said pivotal section to be movable between a first stable position in which said arcuate sections are held open and a second stable position in which said arcuate sections are held closed.
 15. The method of manufacture of claim 10, comprising providing a hinge to form said interconnection.
 16. The method of manufacture of claim 10, comprising providing oppositely facing hooked contours to form said interconnection.
 17. The method of manufacture of claim 16, comprising arranging said pivotal section to be pivotally connected at either side thereof to respective locking surfaces at either end of said second arcuate section to tension respective hooked contours radially outwardly against corresponding hooked contours of said first arcuate section.
 18. The method of manufacture of claim 10, wherein the openable jewelry item is one member of the group consisting of a bracelet, a bangle, a ring, an earring, a finger ring, and a watch. 